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  <meta charset="UTF-8">
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  <title>Document</title>
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<body>
  <script>
    const list = ['a', 'b'];
    const ret = list.push('c');
    // ret = []  push方法返回了源数组
    // ret = 3  push方法返回的数组的长度

    console.log(ret);
    {
      list: list.push('c')
    }
  </script>
</body>

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